Neighborhood Greenway FAQ

1. Why more space for people using bikes?

It is in everyone’s best interest to reduce dependency on single occupant auto trips.

Congestion

PBOT is responsible for helping all residents of Portland move about the city. With an expected 130k+ increase (+20%) in population over the next 20 years, it is unlikely residents will be willing to tear down homes to widen roads for everyone to be able to drive. Providing alternatives to driving will be key to reducing maintenance costs and congestion in the future. Neighborhood Greenways, like SE Lincoln, are part of the solution to reducing future congestion by enabling those that want to use a bike to comfortably travel about the city instead of a car. It is in everyone’s best interest to reduce dependency on single occupant auto trips. See: Transportation System Plan introduction (found in 2007 TSP documents)

Pollution

Portland has an adopted strategy to reduce greenhouse gas emissions. Helping residents to safely walk, bike and use transit for a variety of trip lengths means fewer cars emitting pollution to move the same, or more, people around our city.

Safety

PBOT is changing the way it looks at road safety. The traditional method of only spending taxes where crashes have occurred in the past means we will always be chasing problems. Vision Zero refocuses efforts toward finding solutions for common problems and systemically applying those solutions to prevent future crashes from occurring. Examples of this include:

Pedestrian medians in center turn lanes.

Signals along school routes getting protected lefts.

All signals getting protected left turns.

Modern roundabouts at high crash intersections.

New crosswalk upgrade standards.

Community Health

City Council adopted the Portland Plan in 2012 as a road map on how to improve all aspects of Portland. It includes goals to improve the health of Portland residents, and the exercise and improved safety greenways offer are part of that goal.

2. What is a Neighborhood Greenway?

A Neighborhood Greenway is the label PBOT uses for a system of local auto streets for cyclists to use as collector streets that parallel busier arterial auto streets. Many cyclists do not feel comfortable riding on the busier auto streets and Neighborhood Greenways give cyclists through streets in the same way arterials streets serve such needs of motorists. The ideal goal is to create linear park-like environments for walking and biking. The roadways are intended to be shared by people driving cars and people riding bikes. Safety of cyclists is prioritized on Neighborhood Greenways because of the shared environment. To encourage use by people riding bikes, an ideal goal of 1,000 auto trips per day, with a maximum of 2,000 per day, along with 85th percentile auto speeds of 17-23 mph are the target metrics.

3. What is the 1,000 vehicles per day related to?

As part of its assessment of Neighborhood Greenways (download pdf), PBOT identified a set of traffic volumes as measurements of success. 1,000 auto trips per day was established as the ideal goal for the number of cars daily using a street that families would be encouraged to use by bike. The 1,000 auto trips per day standard is about the same as cyclists being passed by a car less than once a minute. When an existing or proposed greenway route has a car volume below 1,000 vehicles per day, no diversion of auto traffic will be proposed. When a proposed greenway route has more than 1,500 auto trips per day, diversion may be considered. If auto volumes on a proposed greenway exceed 2,000 per day, diversion of auto traffic shall be considered.

4. Will my side street see more traffic because of the project?

Many greenways are traditional through streets in a neighborhood, even though their designation is the same as the other nearby streets. The reasons one street is used more than others often involves fewer stop signs along that path, or the presence of signals at crossings of higher order roadways, both of which attract users. Diversion on a greenway redistributes local traffic amongst the local streets so all the local streets in a neighborhood share the load more evenly, and it is expected that the total volume of through traffic in a neighborhood will go down after diversion is implemented. Diversion along a greenway is expected to move traffic to other nearby streets. Since diversion on Neighborhood Greenways was adopted as part of the Neighborhood Greenways assessment report, a maximum threshold was established for side streets near the greenway to reduce the impact to adjacent residents. Since 1,000 car trips per day was the chosen ideal volume for bike use, this number is also used as the permitted maximum volume on any adjacent side street as a result of a project. This is not an increase of 1,000 cars per day, but a total post-project volume. So, if your street only has 300 current daily trips, it could see another 700. But if your street already has 800 daily trips, the available space is only 200 more daily trips. PBOT uses pre-project counts to help decide where to place diversion, preferring to place it where there is more capacity to absorb diverted drivers.

5. What happens if my side street ends up with more than 1,000 daily trips after the project?

PBOT takes numerous counts away from the project street to gauge the effects of the project on the nearby local streets. If a side street has a post project volume above 1,000 daily trips, and it did not have a pre-project volume problem, PBOT will do follow-up counts to confirm the change is not random, and propose mitigation should a problem remain. The most common mitigation is adjustment of stop signs, traffic calming on the secondary street, diversion on a secondary street and modification of the primary greenway project.

6. What if I live on a side street that already has too much traffic?

The focus of a Neighborhood Greenway project is the greenway. PBOT can review other issues in a neighborhood that may be related to the operation of the greenway, but will focus greenway resources on improving the greenway to encourage bike use along that path. Other traffic concerns should be directed to (503) 823-SAFE, or the PBOT web site.

7. I don’t like speed bumps. Can we have more diverters?

PBOT has had good success with speed bumps over the years. Speed bumps are the most effective tool to slow speeding auto traffic. It has been suggested that more diverters, maybe every ¼ mile (about every 5 blocks) would do the trick. PBOT’s experience shows that 5 blocks are enough distance for people driving to accelerate faster than 25 or 30 mph. PBOT can, sometimes, phase in bumps in groups, measuring to see if diverters alone are doing the job, but it is uncommon that this works.

PBOT has experimented with fire truck friendly speed bumps and continues to explore ways to slow speeding motorists with minimum delay to people biking.

8. I don’t like diverters. Why can’t we have just speed bumps and signs?

Speed bumps are the most effective tool to reduce speeding drivers, but PBOT has a goal of also reducing the number of cars along a greenway so that families feel comfortable riding around. PBOT has had mixed results affecting traffic volume using just bumps, so does not rely on them to reduce traffic volume. Traffic engineers also have a saying: “If signs fixed things, you wouldn’t need traffic engineers”. Any regulatory sign requires regular and random enforcement presence to be effective. Such presence is not predictable and is also expensive.

9. What about Emergency Vehicle Access?

PBOT works closely with Portland Fire and Rescue (PF&R) to minimize delay for fire response. As part of joint testing efforts, the largest and heaviest fire trucks were found to be the most affected by speed bumps and traffic circles. Almost all diverters proposed will be designed so that a fire truck can drive over, or past, the diverter along a similar path the driver would normally take, and all proposed diversion is reviewed by PF&R. PBOT and PF&R have also worked over the years to develop a major and secondary response route network to minimize delay on the pathways fire trucks use the most. New traffic calming and diversion are not permitted on major response routes and only fire friendly speed cushions are permitted on secondary response routes.

Lincoln Greenway Questions

1. Why Harrison-Lincoln? Aren’t there other streets with greater needs?

Traditionally, PBOT has modified a street for livability concerns and moved on. It has been uncommon for PBOT to go back to a street and upgrade to current standards, even when those standards are significantly different than with the original project. In 2015, PBOT initiated an assessment of all greenways, formerly called bike boulevards, to get a snapshot of how the streets were performing for cyclists, based on the draft metrics developed in 2009. The assessment report identified six former bicycle boulevards (legacy greenways) that carried a significant amount of bike traffic, and had high car volumes and speeds. These legacy greenways included:

SE Clinton, 12th to 50th, is complete, and SE Ankeny, 12th to 28th, is pending completion. NE Tillamook was to be next, but a Bureau of Environmental Services project in the west end would have conflicted with the greenway project. NW in Motion is in the planning stages, which leaves Lincoln-Harrison-Ladd and Alameda as the remaining legacy greenways identified for future upgrades.To be sure, there are many parts of Portland with bike infrastructure needs, and PBOT is currently pursuing over a half dozen ‘new’ greenways east of 82nd Avenue, as well as continuing to identify missing links in the current system and plan enhancements on other legacy greenways.

2. Why is Harrison becoming a collector street?

SE Harrison, 26th to 30th, as well as 26th south of Harrison and 30th north of Harrison are already designated as Neighborhood Collector streets in Portland’s Transportation System Plan (TSP). The Harrison-Lincoln Greenway project is not changing any traffic classifications.The purpose of Neighborhood Collector traffic streets is to provide a connection between lower classified Local Service streets and higher classified streets. The TSP does not define traffic streets by how much traffic uses them, since cities grow and shrink, but instead on the function they are meant to serve for a variety of modes. Portland has Neighborhood Collectors with hundreds of car trips daily and a few with thousands of car trips daily. It all depends on where the collector is and nearby land uses.The next higher classification, District Collector, are the streets meant for traffic moving between districts in the city and meant to serve through traffic over longer distances. SE Hawthorne west of 50th is a District Collector.

3. Why only three diverters?

PBOT is still evaluating the effectiveness of diversion internal to a Neighborhood Greenway. PBOT has traditionally only placed diverters at major cross-streets. Internal diversion creates more inconvenience for residents inside the local area, and PBOT is expanding its knowledge about how different forms of diversion interact with neighborhood traffic patterns. On SE Clinton, 12th to 50th, two new diverters were added to the two existing semi-diverters at Chavez, bringing the total to four along a 2-mile corridor. The results on SE Clinton have been better than expected. The SE Ladd/Harrison/Lincoln corridor is three miles long and four new diverters are proposed to be added to the existing three, for a total of seven diverters.

4. How did diversion affect streets along the Clinton Greenway?

Area side streets near Clinton were monitored in the same way as streets near Harrison-Lincoln. After the two new diverters were installed, PBOT measured one block of one street, SE Woodward, that exceeded the 1,000 trips per day standard. PBOT provided traffic calming between 26th and Chavez to mitigate for that traffic increase. Post project counts on SE Woodward have been reduced to acceptable diversion standards. Traffic volume increases on other side streets ranged from reductions of over 100 daily trips to increases of up to 400 daily trips.

Additionally, auto use along Clinton has reduced by more than 30% (-900+ cars) while bike use has been similar or increased. The largest increases were measured west of 20th, exceeding a 30% increase in cyclists in May of 2016.

5. The diverters at 50th will only make things worse on side streets east of 50th.

Adding diversion on Lincoln at 50th changes how local residents can get to their homes, it does not eliminate access. From a general circulation perspective, not all residents from 50th to 60th, between Division and Hawthorne should be using Lincoln as their primary access point. Those closer to Hawthorne should be using Hawthorne, while those closer to Division should be using Division. Lincoln has the same designation as all the less busy side streets it crosses. For years now, residents living along Lincoln have had to deal with too much traffic on their Local Service street, while residents elsewhere in the neighborhood have benefited from this inequity.

As with any Neighborhood Greenway project, streets near the proposed diverters will be monitored for traffic increases. Like Woodward Street near the Clinton greenway, excessive diversion will be mitigated.

6. What about Emergency Vehicle Access?

PBOT works closely with Portland Fire and Rescue (PF&R) to minimize delay for fire response. As part of joint testing efforts, the largest and heaviest fire trucks were found to be the most affected by speed bumps and traffic circles. Almost all diverters proposed will be designed so that a fire truck can drive over, or past, the diverter along a similar path the driver would normally take, and all proposed diversion is reviewed by PF&R. PBOT and PF&R have also worked over the years to develop a major and secondary response route network to minimize delay on the pathways fire trucks use the most. New traffic calming and diversion are not permitted on major response routes and only fire friendly speed cushions are permitted on secondary response routes.

7. You’re blocking my access.

Harrison between 20th and 30th has 26 current access points from higher order streets, and one is proposed for entry restriction.

Lincoln between 30th and Chavez has 29 current access points, and one is proposed for entry restriction.

Lincoln between Chavez and 50th has 32 current access points, and one is proposed for entry restriction.

Lincoln between 50th and 60th has 16-18 current access points, and one is proposed for entry restriction.

So, of the 103 current access points to the Harrison-Lincoln portion of the project, 4 access points (4%) are proposed for half closure. The longest extra distance for a local resident to travel to one of those access points is about ½ mile, and at 25 mph (33 feet per second) the extra time to do so would be about a minute and a half.